TY - JOUR
T1 - Is It Possible to Develop Complex S-Se Graded Band Gap Profiles in Kesterite-Based Solar Cells?
AU - Andrade-Arvizu, Jacob
AU - Izquierdo-Roca, Víctor
AU - Becerril-Romero, Ignacio
AU - Vidal-Fuentes, Pedro
AU - Fonoll-Rubio, Robert
AU - Sánchez, Yudania
AU - Placidi, Marcel
AU - Calvo-Barrio, Lorenzo
AU - Vigil-Galán, Osvaldo
AU - Saucedo, Edgardo
N1 - Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/9/11
Y1 - 2019/9/11
N2 - This work presents the development of a novel chalcogenization process for the fabrication of Cu2ZnSn(S,Se)4 (CZTSSe or kesterite)-based solar cells that enable the generation of sharp graded anionic compositional profiles with high S content at the top and low S content at the bottom. This is achieved through the optimization of the annealing parameters including the study of several sulfur sources with different predicted reactivities (elemental S, thiourea, SnS, and SeS2). As a result, depending on the sulfur source employed, devices with superficially localized maximum sulfur content between 50 and 20% within the charge depletion zone and between 10 and 30% toward the bulk material are obtained. This complex graded structure is confirmed and characterized by combining multiwavelength depth-resolved Raman spectroscopy measurements together with in-depth Auger electron spectroscopy and X-ray fluorescence. In addition, the devices fabricated with such graded band gap absorbers are shown to be fully functional with conversion efficiencies around 9% and with improved VOC deficit values that correlate with the presence of a gradient. These results represent one step forward toward anionic band gap grading in kesterite solar cells.
AB - This work presents the development of a novel chalcogenization process for the fabrication of Cu2ZnSn(S,Se)4 (CZTSSe or kesterite)-based solar cells that enable the generation of sharp graded anionic compositional profiles with high S content at the top and low S content at the bottom. This is achieved through the optimization of the annealing parameters including the study of several sulfur sources with different predicted reactivities (elemental S, thiourea, SnS, and SeS2). As a result, depending on the sulfur source employed, devices with superficially localized maximum sulfur content between 50 and 20% within the charge depletion zone and between 10 and 30% toward the bulk material are obtained. This complex graded structure is confirmed and characterized by combining multiwavelength depth-resolved Raman spectroscopy measurements together with in-depth Auger electron spectroscopy and X-ray fluorescence. In addition, the devices fabricated with such graded band gap absorbers are shown to be fully functional with conversion efficiencies around 9% and with improved VOC deficit values that correlate with the presence of a gradient. These results represent one step forward toward anionic band gap grading in kesterite solar cells.
KW - CuZnSn(S,Se)
KW - V deficit
KW - band gap grading
KW - kesterite
KW - thin-film solar cells
UR - http://www.scopus.com/inward/record.url?scp=85072056547&partnerID=8YFLogxK
U2 - 10.1021/acsami.9b09813
DO - 10.1021/acsami.9b09813
M3 - Artículo
C2 - 31426633
AN - SCOPUS:85072056547
SN - 1944-8244
VL - 11
SP - 32945
EP - 32956
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 36
ER -